Knife sharpener for fabric cutting machines



Aug. 13 1935. A. slMoN 2,010,967

KNIFE SHARPENER FOR FABRIC CUTTING MACHINES i Filed oct. 2s, 1954 F13. E F43@ 5 17/ Z6 23 'j [el 9 INVENTOR, .55 raa/m/.fi/mom M a @MN A a ATTORNEY.

Patented Aug. 13, 1935 UNITED STATES PATENT OFFICE Abraham Simon, Far Rockaway, N. Y. Application October 23, 1934, Serial No. 749,530

3 Claims.

This invention relates to improvements in knife the long vertical knife of va cutting machine to draw an emery stick downward alternately along each side of the knife blade to form a razor-like edge. This method of sharpening has been found unsatisfactory due to the fact that it is impossible for the operator to exert an even pressure on the stick at all times as it strokes both sides of the steel knife blade. It has also been proposed to sharpen the lower cutting edge of the knife with alternately engaging emery blocks either by removing the vertically reciprocating knife from its groove or else by attaching a separate grinding mechanism to the cutting machine whenever there is need for sharpeningthe knife blade.

The present invention is an improvement over the foregoing methods of sharpening and enables the operator to emciently sharpen the entire effective length of the knife blade in a very 'simple manner. More specifically, the invention provides an arrangement which is permanently attached to the upper part of the cutting machine and easily movable into and out of working position by the release of a latch. For sharpening purposes there are provideda pair of blocks made of emery or other suitable abrasive material which respond to the movement of a handle to rotate in opposite directions and simultaneously travel over the effective length of the vertical blade.

Referring to the accompanying drawing wherein like reference numerals indicate like parts, Fig. 1 illustrates a side view of a fabric cutting machine equipped with the Sharpener of the present invention. Fig. 2 is a vertical section taken along the line 2-2 of Fig. 1; and Fig. 3 is a horizontal section taken along the line 3-3 of Fig. 1.

In Fig. 1 there is illustrated in conventional manner a cloth cutting machine comprising an electric motor I0 mounted upon an upright channeled standard Il which is fixed *o a base I2. A vertically reciprocating knife blade I3 is arranged to slide freely in a channel in the forward edge of standard II from which it projects for about half its width. A knife guard I4 serves to protect the operator and is adjustable over the length of the knife blade.

Attached to the front of the motorl housing, is a frame composed of two hollow metallic mounting-s I5 and I6 through which run vertical shafts I1 and I8. These mountings are firmly held together by a metallic cross piece 5I which may be v the chain 31 in its circular travel.

secured to the mountings in any suitable manner such as by screws, not shown. Shafts I1 and I8 are of rectangular shape and serve to rotate emery blocks I9, 20 in response to movement of bevel gears 22, 23 which engage with gears 24, 5 25, the latter of which are linkedtthrough shaft 2'6 and gears 21, 28 to shaft 43 and handle 2|. A pair of surrounding jackets 46 and 41 enable vertical motion of rotating shafts I1 and I8. These shafts rotate in opposite directions and drive gears 29, 30 which respectively engage with gears 3|, 32 for simultaneous motion of emery blocks I9 and 28 which contact with the edge of knife I3. Blocks I9 and 20 are given a slight degree of freedom of movement by means of theirv supporting shafts 33 and 34 which are arranged to be somewhat loose in their bearings. A pair of adjustable coil springs35, 36 bear on the shafts and tend to cause the grinding blocks to exert pressure on the knife I3.

An endless chain 31 driven by a sprocket wheel 38 enables vertical movement of the entire assemblage by virtue of a thin blade 39 which is attached by means of a pinion to one of the links of the endless chain and moves upward and downward as the chain rotates. The lower end of 39 is fastened in any suitable manner to the metallic member 40 which houses `the gearing for thel emery blocks. A second sprocket wheel 4I guides Mounting I5 supports a pair of shafts 442 and 43, the former driving sprocket wheel 38 and linking this wheel with shaft 43 through gears 44, 45. Shaft 43 extends through mounting I6 and is driven by handle 2l Mountings Vl5 and I6 and cross piece 5I are swingingly mounted upon a pivot 52 which in cooperation with spring 48 cause the sharpening mechanism to bear on the knife blade. A latch 49 adapted to engage with pin 50 functions to contract spring 48 and to-cause the entire assemblage to pivot in the opposite direction to free the knife I3 from pressure. Of course, this latch may be dispensed with and any other suitable arrangement employed for vrelieving the pressure on the knife blade. For example, a wedge may be used at the top of the vertical travel of the emery blocks to separate them so as to prevent contact with the knife.

When the Sharpener is not being used, emery blocks I9 and 20 and their associated driving gears are held in their uppermost vertical position near the top of the knife so as not to interfere with the vertically reciprocating motion of the knife. 55

In the operation of the sharpener, a turning of the handle will cause shaft 43 to rotate, in turn, inducing the emery blocks to rotate in opposite directions to sharpen the knife. At the same time shaft 43 will drive endless chain 31 and cause the two blocks i9 and 20 and their rotating shafts I1 and i8 to move vertically along the length of the knife in an upward and downward direction.

It will be understood, of course, that the details of construction can be modied in various ways without departing from the spirit and scope of the invention. If desired, handle 2| may be dispensed With and shaft 43 connected up with motor I in any suitable manner known to the art such as by pulleys.

What is claimed is:

1. 'Ihe combination with a fabric cutting machine having a vertically reciprocating knife,l of a sharpening device attached to said machine, comprising a pairA of abrasive surfaces one on each side of said knife, and means for rotating said surfaces in opposite directions and for simultaneously and continuously moving said surfaces vertically along the length of said knife.

2. The combination with a fabric cutting machine having a vertically reciprocating knife, of a sharpening device attached to said machine comprising a pair of circular blocks of abrasive material placed edge to edge'substantially in the same horizontal plane, one on each side of said knife and in engagement therewith, a pair of vertical shafts for rotating said blocks in opposite directions, and means for simultaneously and continuously raising and lowering said shafts and blocks along the length o f said knife as said blocks rotate.

3. The combination with a fabric cutting machine having a vertically reciprocating knife, of a sharpening device attached to said machine comprising a pair of circular blocks of abrasive material placed edge to edge substantially in the same horizontal plane, one on each sideof said knife and in engagement therewith, a pair of vertical shafts for rotating. said blocks in opposite directions, a handle, gears linked to said handle and responsive to movement thereof for rotating said vertical shafts about their axes, an endless chain also linked to said handle through additional gears and arranged to travel in a vertical plane in response to movement of said handle, a supporting housing for said circular blocks, and means aixed to said housing and pinioned to said chain for raising and lowering said blocks as said chain travels.

ABRAHAM SIMON. 

